c++ - ld 的奇怪警告

Question

我从 ld 收到了这个警告当我构建我的程序时:

ld: warning: direct access in global constructors keyed to _ZN12_GLOBAL__N_143ensure_log_is_created_before_maing_l_filterEto global weak symbol vtable for cs::ObjectFactoryAliasInstantiation<cs::DefaultCommandDispatcher> means the weak symbol cannot be overridden at runtime. This was likely caused by different translation units being compiled with different visibility settings.

错误的代码是这样的:

class ObjectFactory {
        public :
        ObjectFactory(const char *alias):sAlias(alias){};
        std::string sAlias;
        virtual void* createInstance() = 0;
    };

template <class T>
class ObjectFactoryAliasInstantiation : public ObjectFactory{
public:
    ObjectFactoryAliasInstantiation(const char *alias):ObjectFactory(alias){};
    void* createInstance() { return (void*)new T(&sAlias); };
};`

还有这个:

        /*
         Class for register the dispatcher for the command
         */
    class CommandDispatcherRegister {  
    public:
        CommandDispatcherRegister(ObjectFactory *commandFactory);
    };

    /*
     Macro for help the Command Dispatcher classes registration
     */
#define REGISTER_AND_DEFINE_COMMAND_DISPATCHER_CLASS(CMD_CLASS_NAME)  class CMD_CLASS_NAME;\
static const CommandDispatcherRegister CMD_CLASS_NAME ## CommandDispatcherRegister(new ObjectFactoryAliasInstantiation<CMD_CLASS_NAME>(#CMD_CLASS_NAME));\
class CMD_CLASS_NAME : public CommandDispatcher\

结束这个:

 REGISTER_AND_DEFINE_COMMAND_DISPATCHER_CLASS(DefaultCommandDispatcher) {
        bool deinitialized;

Answer 1

这可能是由于使用不同的可见性设置编译的不同翻译单元造成的。

即您更改了一些 header 并且没有对整个项目进行完整 重建。现在就做。